This tie-up "will create one of the world's main companies in the sector," said Gamesa president Ignacio Martin during a special general assembly at its headquarters in Zamudio in northern Spain.

Gamesa will have a 41 percent stake in the merged entity with Siemens holding a majority 59 percent share.

The new group is expected to have a turnover of around 10 billion euros ($10.9 billion), with an order book worth some 22 billion euros and a capacity of 70 gigawatts.

Martin will become the chief executive of the new group, which will be headquartered in Spain and listed on the Madrid stock exchange.

The new company should appear in the first quarter of 2017, once it has the green light from the competition authorities, Martin said.

He stressed that it was "a merger of equals", even if technically the deal will be in the form of a takeover by Siemens.

Gamesa's deal with Siemens, announced in June, came after the company underwent a deep restructuring following a move by the Spanish government to slash subsidies for electricity from renewable sources as Madrid battled an economic crisis.